A.always less than atmospheric pressure
B.always unity
C.an index of molecular position of gas
D.dimensionless
If the temperature of the sink is decreased, the efficiency of a Carnot engine
A.decreases
B.increases
C.remain unaffected
D.first increased and then decreases
COP of the engine is
A.2.33
B.3.33
C.4.33
D.5.33
Power required for the engine is
A.6.60 kW
B.7.75 kW
C.8.88 kW
D.9.23 kW
A 500 litre tank contains a saturated mixture of steam and water at 300?C. If the mass of steam and water within the tank is equal, it can be concluded that
A.Volume of steam will be less than the volume of water
B.volume of steam will be less than the volume of water
C.Steam will be nearly dry and saturated
D.Dryness fraction of steam will be closer to 0.5
Five people must be lifted in an elevator to a distance of 100 m. The work is found to be 341.2 kJ and the gravitational acceleration is 9.75 m/s2. The average mass per person is
A.65 kg
B.72 kg
C.70 kg
D.67.5 kg
An elastic sphere of 0.5 m diameter contains a gas at 115 k Pa. Heating of the sphere causes it to increase to 0.62 m and during the process the pressure is proportional to the sphere diameter. The work done by the gas will be
A.7.7 kJ
B.9.9 kJ
C.11 kJ
D.15 kJ